8th math test

Test 

1. What will be the unit digit of the squares of the following numbers?

(1) 81

(ii) 799

(iii) 1234

(iv) 26387

(v) 526

2. The following numbers are obviously not perfect squares. Give reason.

(ii) 23453

(iii) 7928

(iv) 222222

(v) 64000

3. The squares of which of the following would be odd numbers?

(1) 456 , 345

4. Without adding, find the sum.

1+3+5+7+9+11+13+15+17+19

5.  Express 121 as the sum of 11 odd numbers.

6 How many numbers lie between squares of the following numbers?

G) 25 and 26.

7. Find the square of the following numbers.

(1) 32

(ii) 35

8. Write a Pythagorean triplet whose one member is.

(1) 6

(ii) 14

9. Find the square roots of the following numbers by the Prime Factorisation Method.

(1) 729

(ii) 400

10 For each of the following numbers, find the smallest whole number by which it should be multiplied so as to get a perfect square number. Also find the square root of the square number so obtained.

(1) 252

(ii) 18

11. For each of the following numbers, find the smallest whole number by which it should be divided so as to get a perfect square. Also find the square root of the square number so obtained.

(1) 252

(ii) 2925

12 The students of Class VIII of a school donated 2401 in all, for Prime Minister's National Relief Fund. Each student donated as many rupees as the number of students in the class. Find the number of students in the class.

13. Find the smallest square number that is divisible by each of the numbers 8, 15 and 20.

14 Find the square root of each of the following numbers by Division method.

(I) 3249

(ii 4489

(Iii) 1024

-(ⅲ) 3481

(iv) 529

15 . Find the number of digits in the square root of each of the following numbers (without calculation).

064

(v) 39062

16. Find the square root of the following decimal numbers.

(1) 2.56

(ii) 7.29

(ⅲ) 51.84

17. Find the least number which must be subtracted from each of the following numbers so as to get a perfect square. Also find the square root of the perfect square so obtained.

(1) 402

(iⅲ) 3250

18 Find the least number which must be added to each of the following numbers so as to get a perfect square. Also find the square root of the perfect square so obtained.

(I) 6412

(ii) 1750

(iii) 252

19. Find the length of the side of a square whose area is 441 m².

20. A gardener has 1000 plants. He wants to plant these in such a way that the number of rows and the number of columns remain same. Find the minimum number of plants he needs more for this.